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Energy Response and Physical Reoperties of NTA* Personnel NeutronDosimeter Nuclear Track Film

Description: This paper reports the chemical and physical properties of the NTA film packet. It correlates with these properties the response of this packet to neutrons of various energies. In this correlation the concept of the track unit is introduced as a basic unit for reporting film-packet response.
Date: March 13, 1961
Creator: Lehman, Richard L.
Partner: UNT Libraries Government Documents Department

THE Epsilon*/Lambda BRANCHING RATIO OF Y*1

Description: Recently a T = 1 resonance in the {Lambda}{pi} system called Y*{sub 1} has been observed with a mass of 1385 Mev. Two types of resonances have been predicted that might relate this observation to other elementary-particle interactions: (1) P 3/2 resonances in the {Lambda}{pi} and {Sigma}{pi} systems predicted by global symmetry corresponding to the (3/2, 3/2) resonance of the {pi}N system; (2) a spin-1/2 Y-{pi} resonance resulting from a bound state in the KN system. The position and width of the observed Y*{sub 1} resonance agree with both theories, but since the spin and parity have not yet been determined, it is impossible at present to distinguish between the two theoretical interpretations.
Date: April 25, 1961
Creator: Alston, Margaret H.; Alvarez, Luis W.; Eberhard, Philippe; Good,Myron L.; Graziano, William; Ticho, Harold K. et al.
Partner: UNT Libraries Government Documents Department

EVIDENCE FOR A T = 0 RESONANCE IN THE V * SYSTEM

Description: In previous letters the authors have reported a {Sigma}{pi} resonance observed through the study of the interaction of 1.15-Bev/c K{sup -} meons in hydrogen in the Lawrence Radiation Laboratory 15-in. bubble chamber. They now wish to report the results of the study of the three reactions: (1) K{sup -} + p {yields} {Sigma}{sup +} + {pi}{sup -} + {pi}{sup -} + {pi}{sup +}; (2) K{sup -} + p {yields} {Sigma}{sup -} + {pi}{sup +} + {pi}{sup +} + {pi}{sup -}; and (3) K{sup -} + p {yields} {Sigma}{sup 0} + {pi}{sup 0} + {pi}{sup +} + {pi}{sup -}. Although reactions (1) and (2) are readily identified and measured, reaction (3) cannot be identified unambiguously. Accordingly, they discuss first the results pertaining to reactions (1) and (2). Nineteen events of type (1) and 13 events of type (2) were observed, corresponding to cross sections of 0.19 {+-} .06 and 0.12 {+-} .05 mb, respectively. In a search for possible {Sigma}{pi} resonances, they have plotted in Figure 1 histograms of the invariant masses of the {Sigma} and each of the three pions in reactions (1) and (2). Figure 1b refers to the {Sigma} and pion of like charge; Figure 1a to the {Sigma} and each of the pions of unlike charge. Since there are two unlike-charged pions in each event, twice as many points appear in Figure 1a as in Figure 1b. The plotted curves are mass distributions expected on the basis of a uniform phase-space population. The histogram of Figure 1b agrees with the phase-space curve, but the {Sigma} and unlike-charged pion distribution appears to exhibit an anomaly, suggesting a concentration of events with a ({Sigma}{pi}) mass of about 1405 Mev. To explore this anomaly in more detail, they use the following representation of the data. Since, according to Figure 1b, ...
Date: April 28, 1961
Creator: Alston, Margaret H.; Alvarez, Luis W.; Eberhard, Philippe; Good,Myron L.; Graziano, William; Ticho, Harold K. et al.
Partner: UNT Libraries Government Documents Department

ELECTRON PARAMAGNETIC RESONANCE IN BIOLOGY

Description: A review of the theories of electron paramagnetic resonance in biology is presented, including a discussion of the nature of the physical observation, followed by examples of materials of biological interest. Iq discussing these examples, information is presented in terms of the nature of the starting material under observation rather than the nature of the magnetic entities observed. The examples proceed from the simpler molecules of biological interest (metabolites, vitamins, cofactors) into the more complex materials (polymers, proteins, nucleic acids) toward cellular organelles (mitochondria, chloroplasts) and, finally, to whole cells, organisms and organs. The observation of photoinduced unpaired electrons in photosynthetic material is described and the various parameters controlling it are discussed. The basic observation is interpreted in terms of a primary photophysical act of quantum conversion.
Date: August 15, 1961
Creator: Androes, G.M. & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department

A STUDY OF RESONANCES OF THE Z-7r SYSTEM

Description: Recently a T = 1 resonance in the {Lambda}-{pi} system called Y{sub 1} has been observed with a mass of 1385 MeV. Two types of resonances have been predicted that might relate this observation to other elementary-particle interactions: (1) P 3/2 resonances in the {Lambda}-{pi} and {Sigma}-{pi} systems predicted by global symmetry, corresponding to the (3,2/ 3/2) resonance of the {pi}-N system, (2) a spin-1/2 Y-{pi} resonance resulting from a bound state in the {bar K}-N system. The position and the width of the observed Y{sub 1} resonance agree with both theories, but since the spin and parity have not yet been determined, they cannot distinguish between the two theoretical interpretations.
Date: May 23, 1961
Creator: Alston, M.H.; Alvarez, L.W.; Eberhard, P.; Good, M.L.; Graziano,W.; Ticho, H.K. et al.
Partner: UNT Libraries Government Documents Department

Primordial Organic Chemistry. I. Compounds Resulting from Electron Irradiation of C<sup>14</sup>H<sub>4</sub>

Description: C{sup 14}-labeled methane, together with a number of other presumed primordial gases of the earth's atmosphere, has been subjected to electron bombardments. The products formed have been examined by paper chromatography, ion exchange chromatography, mass spectrometry, and ultraviolet light spectrophotometry. A number of minor molecules have been specifically identified, and urea has been found as a major component in the absence of added phosphine; the formation of urea is inhibited by added phosphine. Most of the products can be accounted for as discrete molecules, even though they are as yet unidentified.
Date: December 1, 1961
Creator: Palm, Christopher & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

SPALLATION-FISSION COMPETITION IN ASTATINE COMPOUND NUCLEI FORMEDBY HEAVY-ION BOMBARDMENT

Description: Cross sections for neutron-evaporation reactions from compound nuclei produced by bombardment of gold with carbon ions and of platinum with nitrogen ions have been determined. The magnitudes of the cross sections are considerably lower than would be predicted on the assumption that neutron emission is the only important mode of decay of the intermediate nuclei. This observation is explained on the basis of fission competition with neutron emission. To a much lesser extent, charged-particle evaporation is also a competing mode of decay. The arguments presented indicate that fission occurs either with comparable magnitudes in several nuclei in the neutron-evaporation chain, or preferentially in one or two nuclei near the end of the chain, rather than predominantly in the initial compound nucleus. Problems arising from the possible existence of isomers in the odd-odd astatine nuclides are discussed.
Date: November 1, 1961
Creator: Thomas, T. Darrah; Gordon, Glen E.; Latimer, Robert M. & Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department

THE PATH OF CARBON IN PHOTOSYNTHESIS

Description: It is almost sixty years since Emil Fischer was describing on a platform such as this one some of the work which led to the basic knowledge of the structure of glucose and its relatives. Today we will be concerned with a description of the experiments which have led to a knowledge of the principal reactions by which those carbohydrate structures are created by photosynthetic organisms from carbon dioxide and water, using the energy of light. The speculations on the way in which carbohydrate was built from carbon dioxide began not long after the recognition of the basic reaction and were carried forward first by Justus von Liebig and then by Adolf von Baeyer and, finally, by Richard Wilstatter and Arthur Stoll into this century. Actually, the route by which animal organisms performed the reverse reaction, that is, the combustion of carbohydrate to carbon dioxide and water with the utilization of the energy resulting from this combination, turned out to be the first one to be successfully mapped, primarily by Otto Meyerhoi and Hans Krebs. Our own interest in the basic process of solar energy conversion by green plants began some time in the years between 1935 and 1937, during my postdoctoral studies with Professor Michael Polanyi at Manchester. It was there I first became conscious of the remarkable properties of coordinated metal compounds, particularly metalloporphyins as represented by heme and chlorophyll. A study was begun at that time, which is still continuing, on the electronic behavior of such metalloporphyrins. It was extended and generalized by the stimulus of Professor Gilbert N. Lewis upon my arrival in Berkeley. I hope these continuing studies may one day contribute to the understanding of the precise way in which chlorophyll and its relatives accomplish the primary quantum conversion into chemical potential which is ...
Date: December 11, 1961
Creator: Calvin, Melvin (Nobel Prize lecture)
Partner: UNT Libraries Government Documents Department

QUANTUM CONVERSION IN PHOTOSYNTHESIS

Description: A new suggestion is made based on model work associated with similar measurements on the biological material itself. The primary quantum conversion act is an ionization occurring in a charge transfer complex. This is what it amounts to in chemical terms. But this process cannot occur in isolated charge transfer molecules in solution because the products cannot escape from each other. The primary quantum conversion as it occurs in modern photosynthesis can only take place in a laminated structure where the electrons and holes can escape from each other by electron migration and not by atomic migrations. This is the essential feature introduced here which differs from all the previous notions of how quantum conversion occurs in chemistry or biology.
Date: January 1, 1961
Creator: Calvin, Melvin
Partner: UNT Libraries Government Documents Department

BIO-ORGANIC CHEMISTRY QUARTERLY REPORT - MARCH THROUGH MAY1961

Description: The study of meteorite Murray has been reported in previous Quarterly Reports. This report gives further results with Murray, and information on another meteorite, Orgueil. A sample of Orgueil was sent from the Museum National d Histoire Naturelle, Paris. It fell in several pieces over an area of 2 square miles near Orgueil, France, in 1864. The elemental analysis of this meteorite is shown in Table 1. They extracted a 10.07-g sample of this meteorite with water, using the same procedure as that for Murray. The water extracted 1.32 g, which is at least twice as much material as was water-extracted from Murray. The elemental analysis of the water extract is given in Table II and its uv spectrum is shown in Figure 1. From an x-ray diffraction pattern it was determined that the water extract contained mostly MgSO{sub 4} {center_dot} 6H{sub 2}O with some calcium sulfate. Their spectrum (Figure 2) shows a strong SO{sub 4} band at 1100 cm{sup -1}, = strong H{sub 2}O bands at 1650 cm{sup -1} and 3200-3600 cm{sup -1}, and some unidentified peaks at 2300, 1400, and 980 cm{sup -1}. The approximately 8 g of Orgueil left after the water extraction was then extracted with purified chloroform. Approximately 50 mg of yellow material was extracted. Its uv spectrum is shown in Figure 3 and is identical to the spectrum of elemental sulfur. Whatever else may be extracted from the meteorites by organic solvents, the uv spectra show only sulfur.
Date: June 29, 1961
Partner: UNT Libraries Government Documents Department

BIO-ORGANIC CHEMISTRY QUARTERLY REPORT DEC. 1960 THROUGH FEB.1961

Description: The current interest in the subject of fiber optics has brought about, among its many achievements, the development of a new technique for measuring refractive index. An instrument designed as a light-pipe refractometer or rod photorefractometer has been described by Kapany and Pike. these authors have presented both a theoretical study of the phenomenon and experimental results arising from a prototype apparatus. The range of applicability of such a device is limited, however, by the availability of rod materials having suitable refractive indices. In particular, the available solid material which has the lowest refractive index and which is also transparent is fused quartz (n{sub D} = 1.458). For reasons inherent in the geometry of the photorefractometer optics, the use of quartz rods does not permit high sensitivity of measurement on liquids having refractive index values less than 1.44. Aqueous solutions, therefore, are beyond the range of study of a system using solid rods. Kapany and Pike suggested the possibility of replacing the solid rod with a hollow cylindrical glass tube filled with a standard liquid. In this manner the effective refractive index of the light pipe is that of the reference liquid and can be varied over the complete range of refractive index for which liquids are available. Under these conditions the refractive index of the solid tube material now serves as an upper limit to the range of applicability. To date no experimental results using a hollow-tube refractometer have been reported, however. In the study presented here a photorefractometer cell incorporating a liquid light pipe has been constructed, and experimental results are reported on solutions in both water and methanol as solvents. These solutions would not be capable of sensitive refractive index measurement using a solid-rod photorefractometer. In addition, some experiments have been carried out toward determining the refractive ...
Date: April 1, 1961
Partner: UNT Libraries Government Documents Department